1. Field of the Invention
The present invention relates to the frame structure of a bicycle/tricycle and, more specifically, to a headset for bicycle/tricycle, which can easily accurately be installed in the frame structure of the bicycle/tricycle and, which keep the parts secured together for easy installation.
2. Description of the Related Art
FIG. 1 illustrates a prior art headset 1 installed in the frame structure of a bicycle or tricycle. The frame structure of the bicycle or tricycle comprises a head tube 2, a front fork top tube 3 inserted through the head tube 2 from the bottom side, and a handlebar stem 4 fastened to the top end of the front fork top tube 3 to hold handlebars. When the rider turning the handlebars of the bicycle or tricycle, the handlebar stem 4 and the front fork top tube 3 are turned with the handlebars. The headset 1 comprises a top ball cup set 6 and a bottom ball cup set 7. The top ball cup set 6 comprises a cup 8 provided at the top side of the head tube 2, a ball bearing 9 received in the cup 8, a cap 10 covered on the top side of the cup 8, and a split packing member 11 mounted on the inner side of the ball bearing 9. When the handlebar stem 4 pressed downwards against the cap 10 and the split packing member 11, the split packing member 11 is radially inwardly compressed and clamped on the periphery of the front fork top tube 3. At the same time, the tapered face 12 of the split packing member 11 is forced against the ball bearing 9, for enabling the inner race 13 of the ball bearing 9 to be rotated with the front fork top tube 3 relative to the head tube 2. The structure of the bottom ball cup set 7 is similar to the top ball cup set 6.
The aforesaid headset 1 is not easy to install. For example, when installing the top ball cup set 6, it is necessary to put the cup 8 in the top side of the head tube 2 at first, and then to put the ball bearing 9 and the split packing member 11 in the cup 8 in proper order, and then to cover the cap 10 on the ball bearing 9 and the split packing member 11. This installation procedure is time and labor consuming, and must be performed in proper order. Further, regular assembly factories commonly provide different sizes of headset component parts in the inventory for use in different sizes or types of vehicles. Before assembly, the worker must pick up headset component parts of corresponding size or type for matching. Much time is wasted in picking up component parts before each assembly procedure.
The present invention has been accomplished to provide a headset for bicycle/tricycle, which eliminates the aforesaid drawbacks. It is the main object of the present invention to provide a headset for vehicle, which is easy to install.
It is another object of the present invention to provide a headset for vehicle, which keeps component parts arranged in set for easy installation and storage.
To achieve these objects of the present invention, the headset is installed in a frame structure of a vehicle, for example, a bicycle or tricycle. The frame structure of the vehicle comprises a head tube, a front fork having a top tube inserted through the head tube, and a handlebar stem fastened to a top end of the top tube of the front fork to hold handlebars, the head tube having a top annular inside mounting groove in a top end thereof. The headset comprises an annular top bearing mounted in the top annular inside mounting groove of the head tube and peripherally disposed in contact with an inside wall of the head tube, the top bearing having a tapered face disposed on the inside at a top side thereof; a top tightening member shaped like a split ring sleeved onto the top tube of the front fork, the top packing member having a split, a vertical wall portion disposed in contact with the periphery of the top tube of the front fork, a top coupling flange upwardly extended from a top side of the vertical wall portion, a horizontal stop flange extended around a middle part of the periphery of the vertical wall portion, and a hooked retaining portion protruded from a bottom side of the vertical wall portion and hooked on a bottom edge of the top bearing, the horizontal stop flange having a tapered face disposed at a bottom side thereof and fitting over the tapered face of the top bearing; and an annular top cap sleeved onto the top tube of the front fork and covered on the top bearing and the top packing member at a top side and stopped at a bottom side of the handlebar stem, the top cap having an inside annular mounting groove forced into engagement with the top coupling flange of the top packing member.